Rotary pump



- 1,636 259 1927' A. J. SWEENEY ROTARY ruur Filed Aug. 24, 1926 WWW INVENTOR ANDREW 1 swnwsY I ATTORNEYS Patented July 19, 19 27.

' UNITED STATES ANDREW T. SWEENEY, F BAYONNE, NEW JERSEY.

ROTARY PUMP.

Application filed August 24, 1926. Serial No. 131,174.

The present invention relates to improvements in pumps or motors of the rotary type.

An object of the invention is to provide a pump wherein the fluid pressure upon opposite sides of a rotary or movable element is equalized or balanced so as to reduce the degree of friction and attain a more efiicient operation of the pump.

As an example of one embodiment of my in invention I have shown the same applied to a well known type of pump in which a toothed rotor is disposed in mesh with a toothed idler, the rotor being driven from an external source. In this type of pump lo the plain faceof the rotor revolves adjacent -to a wall of the pump casing, the pressure being effective on the opposite side gives the rotor a lateral "thrust causing a relatively great amount of friction, often resulting in a retardation in the rate of speed of the rotor with a consequent loss in efficiency.

It has been proposed to equalize the pressure upon both sides of a rotor of the abovementioned type by admitting the pressure fluid to the entire rear surface of the rotor, but owing to the necessary clearance between the wall of the casing and the periphery of the rotor communication was afforded be- ?tween the'high and low pressure sides of the pump, thus defeating the effectiveness of the admittahce of pressure to the opposite area of the rotor,

In the present invention I provide the rotor with a series of apertures in the form of radially disposed slots and the opposed side of the casing with pockets or cells td receive fluid .under pressure. As the rotor re volves the fluid enters the cells and is en trapped, thus serving to balance the rotor and also acting as a cushion to the end that friction is reduced to a minimum.

The invention will be more fully understood by reference to the accompanying drawings in which I 1 i Fig. lis a sectional yiew iii-elevation of a rotary pump of a Wellkn'owntype modified in accordance withthe present invention.

Fig. 2 is a transverse sectional view of the pump taken'on line II-II in Fig 1.*

Fig. 3 is a view of the rear side of. the rotor showing the radially disposed apertures in the disk thereof, and

Fig. 4 is a view of the interior of the casiig showing cells to receive pressure fiui The pump selected to illustrate an embodiment of my invention comprises a casing or cylinder 5 having a dividing wall 6 separating the easing into two chambers 7 and 8 in which are disposed an idler or follower wheel 9 and a rotor 10, respectively.

The follower wheel is provided with teeth 11 extending radially from the peripher of the wheel. The teeth may be slig itly tapered so that the root of each tooth is of greaterwidth than the summit. The idler 9 has a running fit with the chamber and is provided with a centering boss 12 to fit a recess 12 which may be provided in the coverv 13 of the casing, suitable packing being provided to prevent leakage. A mounting for the wheel 9 is provided in the form of a stub shaft 14 mounted in the dividing wall 6 and in the cover.

At the side of the casing opposite to that having the chamber 7 is the chamber 8 and a portion of the wall dividing the chambers is removed so that the chambers intersect tangentially as shown in Fig. 2. At the point of intersection of the chambers is a contact face or abutment 15 which in conjunction with the rotary elements separates the two chambers.

The rotor or driving element 10 is in the form of a disk 16 provided witha hub 17. 95 fitting a recess in a head or wall 18 of the casing, suitable packing being provided to prevent leakage. The rotor is keyed to a shaft 19 mounted in a bearing in the wall 6.

The disk 16 of the rotor 10 is provided with a plurality of teeth 21 disposed ad jacent to the perimeter of the disk and these teeth are arranged to mesh with teeth 11 on the idler 9. It will be evident that the teeth when in inter-meshing contact operate in conjunction with the abutment 15 to prevent the passage of fluid from one side of the chamber to the other.

In the upper and lower portions of the cas-. ing are ports 22 and 23, respectively, extending on tangential lines from the annular chamber 8 and either-port may serve as an inlet or an outlet.

Forthe purpose of attaining a proper balance of the rotor when the device is used to take in fluid at atmospheric pressure and discharge at about 150 to 200 pounds, I provide the disk 16 of the rotor with a plu rality .of radially disposed slots 24 and the wall or head 18 with pockets or cells 25.

' When the present device is in use the fluid entering the lower port 23 at low pressure is discharged from port 22 at high pressure but the openings 24 revent the pressure fluid to pass into the cel s and balance the rotor,

the fluid entrapped in the cells serving as a cushion and eliminating friction.

It will be understood that the cells may be of different capacities or their effective areas may be varied in accordance with the area of the disk. The apertures 25 or slots in the disk may, if desired, have a combined area greater than the area of the disk at the side opposite to the cells 25.

By reason of the present improvement a pump employin a rotor as above described may be operate with an equal distribution of pressure thus relieving friction and promoting the eficiency of the device.

The cells 25 may be of graduated capacity from the high to the low pressure side of the pump, or an opposite arrangement may be provided. The degree in variation between the cells may be calculated or determined by experiment to' obtain a smooth gradient of pressure to balance the rotary element and compensate for a difference in pressure over the surface thereof opposed by the pressure in the cells.

Although a preferred embodiment of the invention is shown and described herein it will be understood that modifications may be made therein without departing from the spirit and scope of the invention as defined in the appended claims.

What is claimed is:

1. In a pump or. motor mechanism, a casing having an intermediate dividing wall separating-the interior of the easing into macaw intersecting chambers, a rotatable member adjacent to an interior wall of the casing, said member havin an aperture for the passage of pressure uid therethrough, and a pocket in the wall of the casing to receive and entrap said fluid to equalize the lateral thrust upon said member resulting from the pressure fluid.

2. In a pump or motor mechanism, a casing having an intermediate dividing wall separating the interior of the casing intov intersecting chambers, a rotatable member operable under pressure and rotatable adjacent to an interior wall of the casin said member having a plurality of radial y disposed apertures for the passage of fluid under pressure therethrougn, a plurality of radially disposed pockets in the wall of said casing disposed to register with said apertures to receive and entrap fluid under pressure which serves during a rotation of said rotatable member to balance the same against pressure built up in said device.

In testimony whereof I aflix my signature.

ANDREW J. SWEENEY. 

